The screen is just as strong as the screen in a regular window screen cage, the grove is made by a table saw and like Joe said, the screen is laid out, the spline pressed into the grove holding the screen taut and in place then the excess trimmed. Also, it is very easy to replace should the screen get damaged.
The wood has been stained with a water resistant wax based sealer; this particular cage was done so with a very natural color, if I offer the cages I will likely have a pick your own color option for a fee lest you want a standard color that I have yet to decide on. I will also likely have colored bottoms to choose from.
Price, I want to keep them affordable... A normal 16x30 screen cage can be purchased from LLL for $55; I would likely sell this cage for $80. And of course custom sizes can be made, I plan to make a bakers rack sized cage for all my rack kin, finaly, 3 large sized cages per shelf!